Reflected Light: A clear-cut explanation for painting reflected light 2021

Reflected Light - A clear-cut explanation for painting reflected light

Welcome to Reflected Light with CecelyV!

Hello and welcome, fellow artists! Thank you for taking some time to read my article on reflected light.

There is a lot to understand about The Fundamentals of Light and The Fundamentals of Art, and sometimes it can all feel large and overwhelming. In this article, I’ve broken out reflected light, a small and vital piece of light fundamentals, to explain and demonstrate what it is and how it works.

I hope to help you build your understanding of light one small step at a time, so it all feels less daunting. To make this article helpful, I’ve kept the focus narrow. This article is only about reflected light. I’ll explain what reflected light is and how it’s different from other light effects, and I will give examples and demonstrate how to paint reflected light.

Understanding light

To fully understand how light works, we need to study it. In my Fundamentals of Light article, I explore and explain the basics of light fundamentals. But, first, let’s review a few points that will help with understanding reflected light.

Light source

A light source is anything that produces its own light. Typically, we draw and paint light effects from familiar natural sources such as the sun and fire and artificial sources like light bulbs.

Each light source has its own properties and characteristics, and most produce a lot of heat to emit light. A couple of exceptions are bioluminescence and chemiluminescence, which see light photons produced without much or any heat (“cool light”). We see bioluminescence in fireflies and jellyfish, and we see chemiluminescence in glow sticks.

Reflectors

Objects and organisms that do not create the light that comes from them are called Reflectors. So, for example, our moon, mirrors, eyes, and other things with reflective surfaces are all reflectors–they all reflect light from a light source but do not emit (or produce) any light of their own.

Understanding light means exploring light sources as well as objects that act as reflectors.

Light rays

reflected light - light rays
Rays of strong sunlight

Light always travels in a straight line called a ray. However, the direction of light rays is changed through reflection and refraction, and what I’m covering is fundamental light reflection.

Direct light and Indirect light

For a surface to receive direct light means there is nothing between the light source and that surface. Therefore, the lighting is directly contacting the surface with no interference to affect the direction of the light rays.

Indirect light is light that is being diffused or reflected in some way before it reaches the lit surface–its direction is changed. This means before light hits an object’s surface, there is quite a lot of light bouncing around off other surfaces.

A sunny day experienced through a bedroom window is an example of indirect light. The sun’s light is being diffused and reflected off clouds, the atmosphere, the ground, the window glass, and the bedroom walls and objects to light the bedroom. The light source, in this case, the sun, is not shining its light directly into the bedroom, but its light is illuminating the room in an indirect way.

Primary light source

In the example of a bedroom on a sunny day, the primary light source is the sun. There aren’t any other light sources acting on the bedroom in this scenario. When light bounces off so many surfaces to illuminate an area like that it’s also an example of ambient light.

When lighting a scene, the primary light source is the strongest (most intense and bright) light source that is responsible for most or all of the light and shadows occurring. A primary light source can be any type of light as long as it is the main source of lighting.

Secondary light sources tend to be smaller, closer to the subject, less intense, and less bright.

What is reflected light in art?

Reflected light in art is the same as reflected light in nature. The only difference is nature doesn’t need tutorials like we do 😉.

Reflected light happens when light emitted from a source bounces (or reflects) off objects and surfaces and illuminates other areas/surfaces/objects with that reflecting light.

Here are some examples of reflected light.

What is the difference between light and reflected light?

Context, intensity, and whether or not absorption is happening are the main differences between the terms “light” and “reflected light.”

Light and reflected light in context

When we refer to light, we’re usually talking about a light source–something that is producing and emitting its own light that we can see. So, when we say, “turn on a light”, “light a candle”, or “hand me that flashlight” we know we’re talking about light sources like lamps, candlelight, or a flashlight.

If you were to walk into a bedroom ambiently lit as in the earlier example, you’d probably say the room appears “bright” because of the light falling through the bedroom window and light bouncing off various reflective surfaces. It’s not likely you’d say, “what a nice bedroom with reflective light.”

So, the context is important. Typically, we don’t refer to most lights as reflected lights unless we are specifically calling out the fact that light is being reflected.

Intensity

There is a significant difference between the intensity of source light and that of reflected light. Source light loses most of its intensity when it begins bouncing around off surfaces and objects, so reflected light is much weaker than the source that creates it.

An exception to this rule happens when light is bounced off a highly reflective surface, such as glass or water.

Absorption

Let’s use direct sunlight as an example. When it is reflected (or bounced) off highly reflective surfaces such as water, glass, or a mirror, direct sunlight loses little to none of its intensity because almost none of the sunlight is being absorbed by those materials. It is all being reflected.

Most reflected light we see has been bounced off surfaces with considerably lower reflectivity than water or glass, meaning much of the light is being absorbed. The absorption results in lost intensity for the bit of light that gets reflected, which is why reflected light appears so much weaker than source light.

What is reflected color in art?

This isn’t really a thing. “Reflected color” is really just light that has reflected off a colored object and taken on the local color of that object, or it’s colored light that is being reflected or both. We cannot see color–or anything else–without light, so there is no such thing as “reflected color” only reflected light that has a color.

What is reflected light in drawing?

Reflected light is the same whether you’re drawing or painting, or observing light in real life. The medium you use to describe light in your image doesn’t change the behavior of light. Reflected light in a drawing is still light that is coming from a source and being reflected off an object or surface to illuminate another area, surface, or object with the light reflected.

The main concept to understand with reflected light is the light’s behavior when it is being reflected, and the materials it is reflecting off of. Technique changes with the medium used, but the behavior of light will remain consistent and predictable.

What is the difference between reflections and reflected light?

The reflectivity of the object/surface material and the light intensity involved is what separates reflected light from what we usually call a reflection. The behavior of the light is the same for both, but the refractive index and reflectivity of materials play a big role in how light’s behavior is conveyed to our eyes.

With reflected light, we see an indication of an object’s reflection on a matte surface, whereas we see clear to mirror-like forms with reflections.

Examples of Reflection vs. Reflected Light

Differences and changes in materials’ characteristics can alter light’s direction and the appearance of reflections. As you can see in the images below, the quality of reflected light and reflections is noticeably different as materials, form, and light intensity change.

Below are more images to demonstrate the differences between reflected light and a reflection.

In the first image, everything above the horizon–sky, clouds, mountains, and treeline–is reflected perfectly on the mirror-like (specular) flat surface of the lake’s still waters.

In the second image, we have much the same effect but with even more reflections happening on the glass sphere. The spheric form and highly reflective–and transparent!–quality of the glass further alter the direction of the light through refraction as well as reflection, so there’s a lot going on there.

The same is true of the third image, but the soap bubble has an additional characteristic of iridescence that drastically alters the appearance of the reflections cast upon its surface.

All three images show highly reflective materials, each with its own sets of characteristics that greatly impact the quality and appearance of the reflections.

The next three images show how changes to the materials can alter the specularity of the reflections, creating more of a Lambertian effect.

In the first image above on the left, we have an evening/night scene with artificial light reflected on the surface of a large body of water. In our earlier example of light reflected off water, we had a daytime scene and still water that created a mirror image of the objects above the horizon line. In this image, the water is not still and the light sources are smaller and less intense.

This change to the material and light intensity creates a Lambertian reflection rather than a specular reflection. The main difference between the two is the texture of the surface material receiving the reflection. The water is still highly reflective, but it is now choppy and textured instead of still and smooth and that creates more of a matte (diffusely reflecting) surface on the water.

Smaller, lower intensity light that is bouncing around more on a now matte surface means we see reflected light on the water rather than reflections of forms.

The next image with a person’s reflection on wet sand applies the same principle. The surface material here is actually wet sand, not water. Sand is not reflective, but soaking wet sand on a shore when the tide is in? That scenario combines the texture of the sand with the reflectivity of the water, and we get a reflection that is somewhere between Lambertian and Specular.

The last image shows a wooden cylinder next to a purple plastic cup. The cylinder has a matte surface, the plastic cup shiny and reflective. When lit and placed near each other, we see reflected purple light (Lambertian reflection) on the wooden cylinder, and a more specular form reflection on the plastic cup.

Notice on the cup we can clearly see the reflection of the wooden cylinder, the light source, and a couple of other items on the shadow side of the cup. All of the reflections on the cup also have a purple tint, reminding us that local color for each object is always a factor.

Understanding how reflected light works

First things first, let’s review some basic light and shadow terminology, shall we? In the image below, I’ve labeled all the stuff and gubbins and you can always refer to my Fundamentals of Light article if you need an in-depth explanation.

We’ve discussed materials, reflectivity, and light intensity as a few factors that affect how light reflects. A couple of other factors to consider when we’re studying reflected light are distance and position.

The next few callout images demonstrate how the distance between objects impacts the amount of reflected light that is able to reach the subject.

In this next round of callouts, I’ll demonstrate more about how object position and materials affect reflected light.

You might have noticed that most of the time when we observe light bouncing onto an object or surface it does so in the form shadow (dark side, shadowed areas) and/or in the cast shadow areas. The reason is all about positioning. When one object is in front of another it will cast a shadow on that object, reflecting little to no light onto it. This is because the light falling on any object will reflect out at the same angle it came in (Law of Reflection).

In the image with the red box and the wooden cylinder, we see a slight exception because of the proximity of the objects. The intensity of the light, and the proximity of the objects to the light source and to each other, means the light is able to bounce around from the source to the cylinder, to the box, and back onto the cylinder giving the red box’s cast shadow a red tint.

Since materials play such a big role in how light interacts with objects, it’s worthwhile to examine a few more instances of how changes to material characteristics affect everything from form shadows to cast shadows, to the tint and shade of reflections and shadows, and the edge of a shadow or reflection.

Light transmission is a separate but obviously related light effect. When materials are translucent or transparent light is allowed to pass through to varying degrees, and can then bounce around on other objects and surfaces. Since it is a separate area, I won’t lose focus by delving into it here, but I thought it would be helpful to offer a few examples so you’ll know the differences in the light effects you observe as you study and practice the Fundamentals of Light.

How to paint reflected light

I created a basic demonstration that I hope helps bring all this together in a simple example. My demo uses simple matte forms so the focus remains on reflected light. Painting reflections and specularity are a whole other demonstration and require a lot more explanation of additional factors like global illumination, so I’ll save that for another time.

Just a few more points

I wanted to mention a few things about local color, colored light, and shadows. In my examples and demonstration, I focused on how light reflects onto objects rather than in shadows or on surfaces. It’s important to mention that the same behavior happens in shadows and on surfaces as on objects. Even a dark shadow can be illuminated with some reflected light, and create interesting visual tonal contrast.

One exception to this, however, is occlusion shadows. The absolute darkest part of any image is where no light can reach– and bounce light is far too weak to penetrate occlusion shadows. Darker shadows will still have color and temperature even if they aren’t illuminated in any way (shadows aren’t really black), and they are still impacted by the local color of the object casting the shadow and the surface the shadow is being cast upon.

When the light source is a colored light, like blue light or the yellow light of the sun, the hue and temperature of the shadows and bounce light will be affected. Of course, we must still account for light intensity and changes to materials.

These are all things we should keep in mind as our understanding and practice of lighting effects grows, and there are a lot of moving parts. If it feels overwhelming, just break down your practice into smaller steps with fewer factors and build up over time.

At first, I recommend tackling basic lighting and simple bounce light on objects, in forms shadows, and in cast shadows with matte materials.

Another Light and Shadow installment, signing off!

As always, Thank you so very much for stopping by my site and reading what I hope you found to be a great article. If not a great article, I hope you found it helpful. If it wasn’t helpful, then yikes! Please let me know that, too, so I can find areas to improve.

If you have any questions, need guidance, or have feedback for me, please send them in the comments section below. I would love to hear from you.

Good luck and best wishes on your practice! Stay safe, take care, and happy drawing!

Light and Shadow in Art – The Fundamentals of Light, Part 1: The Science & The Basics Made Clear

light and shadow in art

The Science & The Basics

I’m not sure many people fully appreciate the nature of what artists attempt to do each time we set out to render light and shadow in art. I know I haven’t fully understood it, let alone appreciated it, even as I am in the middle of rendering.

As I continue to really dig into what Light is, I am awestruck and so thankful to all the scientists and artists who came before me—the giants upon whose shoulders we stand—because the subject of Light is huge, and I am glad they already figured all this stuff out for us 😅.

It is difficult not to get philosophical here because what we are really doing when we render light is re-creating the properties and behaviors of light in a 2D space—and those behaviors and properties encompass several sub-branches of modern Physics, including: Quantum Physics, Modern Optics, Geometric Optics, and Physical Optics.

Let’s take a moment to appreciate the fact that different aspects of light behavior and properties come under several different categories of Physics that are each quite involved areas all their own.

That was my not-so-subtle warning that The Fundamentals of Light gets quite technical.

The understanding we gain for our art is totally worth it, and we need three things for sure: 1) Patience, 2) Plenty of visual examples, and 3) More than one post to go through the massive amounts of information.

For any of you who are much better scientists than I, please forgive any inaccuracies in my scientific understanding or explanation. I endeavor to be an expert artist, not physicist 😋 , but I do try to be as accurate and as clear as possible. If I get something wrong, please let me know in the comments and I will do my best to make corrections.

I hope you will hang in there with me as I break down the technical bits (that’s the patience part), I hope the examples and information I share help your practice, and that you’ll find it useful enough to look forward to the future posts in this series. Since this is the first, let’s start digging into to the science, shall we?

The Science—What is Light?

To understand how to render light and shadow we must grasp the concept of what light is and how it behaves.

Light is a type of energy created by the emission of photons within the electromagnetic spectrum. If that sounded like gobbledygook, fear not, I shall explain.

A photon is a “small bundle” of electromagnetic energy and the basic unit that makes up all light. Thus, photons are the building blocks of light.

Electromagnetic energy describes forms of energy that are reflected or emitted from objects as electrical and magnetic waves that can travel through space. The Electromagnetic Spectrum shown below describes these energies as frequencies and wavelengths.

Electromagnetic Spectrum

The light effects we paint represent a fixed and narrow range of the Electromagnetic Spectrum called the Visible spectrum, which is a narrow group of wavelengths between approximately 380 nm (nanometers) and 730 nm.

As illustrated in the diagram above, The Electromagnetic Spectrum contains several other forms of light, however most of them are at frequencies we can feel but not “see”.

All light has both a frequency and a wavelength, and all light can behave as both a particle and a wave depending on the situation. In fact, both light and matter have particle-wave duality in their properties and behavior. It’s important for artists to understand this duality because it affects our thinking and problem solving regarding light at different stages during rendering.

When we begin to invent our images we must also invent our lighting. When we are mentally calculating the direction of our light source, its reflections, and fall off, it is helpful to think of light as particles, or rays, that travel in straight lines.

This helps us figure out how much of our object will be lit, how to place the form shadows and cast shadows, and where the bounce light will land. When objects are opaque, I have found considering light primarily as rays helps me best determine how to render the light.

When objects are translucent, transparent, or have variable reflectivity, things start to get more complex because light is not simply being absorbed and reflected but also transmitted through the object. Transmission of light through objects gives us more to consider and calculate because it gives us more to paint, like subsurface scattering, refraction, and more reflections.

Let me put your mind at ease and say it is not necessary to do any complex mathematic calculations to paint these effects, just some additional concepts to understand and visual calculations to make.

When we think about reflection, refraction, and absorption, it helps to think of light first as a particle or ray (for determining the light’s intensity, direction, and bounce) and then as a wave—for determining which wavelengths are reflected off, absorbed by, and/or transmitted through the object and the ground.

That was a huge mouthful, I know. I will be going over all of these more nuanced areas in other posts in this series.

Understanding the particle-wave duality of light begins to give us a clear view of how light’s behavior changes as it interacts with different materials. Watching the videos below helped me gain a clearer understanding of this concept, and I hope you find them useful, too.

As we bring together the elements we need to understand, we start to define the contours of The Fundamentals of Light so that we can start filling in details and particulars—and don’t worry, there will be photographic examples and demos so all of this becomes more clear.

Properties of Light & Matter for Artists

I know this has been a little science-heavy so far, and that’s intentional. It is how I make sense of complex topics, and I hope you find it helpful. Now that we’ve covered the basics of what light is, I’ll change things up a bit to keep everything digestible. I’ll cover a little science and do some explaining, and then use photographic examples or demos to clarify how the information helps in creating art.

Next, let’s dig into the properties of light, but first I want to give you a list of all the properties to keep in mind whenever it’s time to render light. This is a list according to me, and they’re based on my experience rendering light in both 2D (Photoshop) and 3D (Maya).

Light PropertiesMatter Properties
Number of SourcesForm/Shape
Type of Light(s)Local Color
Size of Source(s)Material Type
Distance from object/picture planeDensity
Angle/Height of Source(s)Reflectivity
Temperature/ColorTransmission
Exposure/IntensityRefractive Index
Fall OffEmission

Some of these are straightforward, so let’s talk about those briefly. The number of light sources is an important consideration because we need to know how much light information we’re working with. More light sources in a scene makes for a brighter image, but how each source affects the picture plane depends on all the other properties on the list.

The size and angle/height of each source are also straightforward properties and they ask questions like: Is a light source large, small, or medium? Do several small lights make up one larger source because of how closely grouped they are? Do these sources sit high or low on the picture plane? Are they even visible in the image, or are they shining from somewhere out of frame?

Under properties of matter, shape, form, local color, and material type are the most straightforward. We must know what shapes and forms make up the volume of the objects we’re rendering, and we need to know what color and material type they are. After all, there is quite a difference between painting a shiny chrome ball and painting a shiny colored plastic ball. Sure, they’re both shiny; but one is metal and ridiculously reflective while the other is plastic, softer, and much less reflective.

The Two Ways Our World is Lit

Despite all the science, properties, and moving parts involved with understanding how objects are lit, there really are only two ways anything receives light in our world: directly or indirectly.

Objects are either lit directly by a light source or indirectly by reflected light when the rays from the source bounce off some surfaces and objects to illuminate others. This kind of indirect lighting is also called Ambient Light and it is much weaker in comparison to direct light. Most lighting schemes will involve both direct and indirect lighting.

Next, we’ll go over the categories that light sources fall into.

Properties of Light – Types of Light Sources

There are 3 types of light sources:

  1. Key Light
  2. Fill Light
  3. Rim Light

Key Light

A key light is the strongest light source in your scene. It defines the emotional impact of the scene and is the primary descriptor of forms and drama. When you decide how to “key” your scene, you are choosing the overall mood and tonal range that will define it.

Fill Light

A fill light is not as bright as a key light and is often softer and a lot darker. Fill lights support your scene and subjects by adding light and color information in the shadows, which can illuminate an area of interest you wish the viewer to see or just provide added interest or balance to your scene. Fill light can be ambient (reflected) light, as I’ve done in my examples below, or it can come from an additional light source(s).

Rim Light

A rim light travels the outer edges of objects. Rim light helps define shapes, add dramatic appeal, and can be a helpful tool for adding compositional information and/or emotional impact.

No matter what kind of mood a story or scene calls for, any lighting scheme will have at least a key light and, likely, some combination of all three light source types.

Okie dokie, how’re you doing? I know this has been a lot to get through, and I hope you’re still hanging in there with me. Deep breaths, we’ve got this!

Now, it’s time to go over some terminology to help keep things clear as we continue to move through the Fundamentals of Light.

Defining Terminology + Sphere Tests

Think of this as the glossary section of this post. Here I’ll define the frequently used terms that will show up quite often from now on in both my writing and the call-outs in demos and examples.

Light Source

Anything that creates and emits light. Light sources can be natural, like the sun, moon, and fire, or artificial, like lamp posts, flashlights, and device screens.

Light Direction & Angle

The orientation of a light source relative to the picture plane. For example, low and out of frame on the left, or mid-level and in frame on the right.

Exposure

The intensity or strength of a light source. A high exposure light source makes for a brighter, “high key” scene, while a lower exposure light will make a scene appear less bright. I tend to use exposure and intensity interchangeably.

Center Light

The area of a form receiving most of the light; the lit side of a form.

Highlight

The brightest area on a form. This is usually a small area that is receiving the most direct light and reflecting a bit of it back.

Half Tone

The area on a form that has begun to turn away from the light source, resulting in a transition area of light to shadow. This area is receiving some light, but not nearly as much as the parts of the form facing the light source more directly.

Reflected/Bounce Light

Light that bounces off a surface and then lands on another form or surface is Reflected or “bounce” light. Reflected light is much weaker than direct light and can occur on any part of a form, except occluded areas.

Terminus/Terminator

The point at which light cannot land on a surface. This is where the shadow side of the form begins.

Shadow Core

The darkest part of the form shadow. The shadow core on a sphere typically looks like a dark band right next to the terminus, a clear separator between the light and shadow. The core shadow is also the part of the form shadow least affected by reflected light.

Form Shadow

The areas of a form that are in complete shadow and receive no direct light.

Occlusion Shadow

Occlusion shadows are the darkest areas in shadows and on/within forms where absolutely no light can reach. When something is occluded it is completely obstructed or blocked, so when light is occluded you have complete darkness.

We see occlusion most often in narrow areas right beneath forms before the cast shadow begins, and with narrow openings, cracks, and crevices of surfaces/forms. Occluded areas are not sufficiently open enough to the environment to receive any light, so there is only shadow.

Cast Shadow

Cast shadows is created when an object’s form blocks light. Objects block light adjacent to themselves and in the shape of their contours. There are three distinct parts to a cast shadow, the Umbra, Penumbra, and Antumbra. Much of the time, in art, we are only painting an umbra and penumbra. When multiple light sources of different intensity and direction/angle are involved, we begin to see examples of all three parts of a cast shadow.

  1. Umbra: Umbra is Latin for “shadow”. The umbra is the innermost and darkest part of a cast shadow, where the light source is completely blocked by the form creating the shadow. [i]
  2. Penumbra: Penumbra is Latin for “nearly” and “almost”. The penumbra is further from the object and lighter than the umbra. Further away from the object light from the source and the environment can influence and brighten the shadows.
  3. Antumbra: The antumbra is the lightest and softest part of a cast shadow. The technical definition is confusing and unnecessary for our purposes, but if you’re curious click here.

Now, I’m going to show a few sphere test examples to visually illustrate the terms above so we can make practical sense of all you’ve been reading.

Basic Light and Shadow Demo 06-add highlight-reflected light
Basic Light and Shadow Demo 07-Sequential

The Distance of Light Sources & Why It Matters

Each property of light plays a role in affecting the mood of our scene and the light effects we paint, including shadows. The appearance and quality of shadows is determined by the light and forms that cast them. How near or distant a light source is to an object has a significant impact on the appearance of an object’s form shadows and cast shadows, so let’s get into that next.

Distant Light Sources (Sunlight, moonlight, spotlights, etc)

We can group lights into categories based on their characteristics, like size, distance, and how intense they are to get a starting place for how those lights would interact with the objects in our scenes.

Distant light sources are things like sunlight, moonlight, and powerful spotlights like those in stadiums and theaters. Distant lights tend to:

  • Be neutral lights.
  • Cause soft-edged form shadows.
  • Create cast shadows that are the same size and shape as the object because their light rays are parallel.

As one example, we know the sun is a huge, very distant, powerful light source, and from observation we know that light from the sun strongly illuminates everything it reaches. That means light is bouncing around everywhere in our atmosphere and reflecting a lot of light, so we can expect brighter and more colorful shadows when the sun is involved.

Playing with exposure also makes a big difference, so an overcast grey sky lowers the exposure, diffuses the light, and makes the sunlight seem much less energetic than a clear and cloudless sky, and creates lighter, softer, and less colorful shadows.

The Sun is also larger than our Earth, and any object we would light with it, so we must also consider the sun as an “oversized” light, which we’ll get into in a minute.

Nearby Light Sources

Nearby light sources are things like lamps, candles, device screens and monitors, lighters, matches, lanterns, etc. Nearby light sources tend to create:

  • Larger cast shadows because the light rays are no longer parallel.
  • Shorter and sharper (harder edged) cast shadows the closer they are to objects, longer and softer cast shadows the further they are from objects.
  • A higher terminus and a larger form shadow.
  • A more active or energetic feel and added tension to a scene.

When nearby light sources are also quite small (like candlelight or a lighter), they tend to cast hard edged cast shadows. They present an additional composition challenge because they can become distracting if not handled carefully. Nearby light sources tend to become a focal point in a scene, so it’s important to be mindful of that and use it to your advantage for your chosen lighting scheme and compositional design.

Oversized or Diffuse Light Sources

Examples of oversized or diffuse light sources are the entire sky on an overcast day (sky light), light coming through large windows, and any light that is scattered by being translucently covered or blocked (like a paper lantern, a light sheet or cloth, an umbrella, or frosted glass covering for light bulbs). Oversize or diffuse light sources tend to:

  • Cause an object’s terminus to move further away from the light source (the larger the light source is larger relative to the object).
  • Create softer edged shadows.
  • Make environments and characters feel softer, warmer, and more friendly.

In the case of light sources that are larger than the objects they illuminate, the light rays are travelling out in random directions, reflecting off the atmosphere and other objects and surfaces, and filling in the shadows, which softens them. Shadows become softer edged because light does not reach each part of the shadow area equally, and because the object blocks (occludes) part of the light area behind it.

Ambient Light

Ambient light is created when light from a source is reflected off the ground, other objects, and the environment. It is possible for objects to be exclusively lit by ambient light, but a key light (which is usually a direct kind of light) is still needed to emit the light that will be reflected.

Terms like indirect light, reflected light, and bounce light all mean the same thing: they are all ambient light. Ambient light is most noticeable in shadows because of the contrast, but it is present whenever and wherever reflected light lands on an object or surface.

Light rays lose most of their strength and brightness (90%) with each bounce, and they are bouncing around multiple times. This loss of strength is why ambient light is generally weak and cannot reach into occluded areas.

You may have come across the term ambient occlusion, especially as it relates to lighting in 3D modeling apps like Maya and Zbrush. In drawing and painting, if zero light can reach an area, I simply refer to this as an occlusion shadow or an occluded area.

For a bit more on ambient light and ambient occlusion, here’s a video by Marco Bucci (awesome artist!) that I found helpful.

Light Direction & Angle: How They Affect A Scene

In any lighting scheme, cast shadows are a compositional and mood element that should be considered and planned. Choosing the light’s direction and angle is an important step in setting the emotional tone of a scene as well as defining forms and helping viewers to understand how to react to what they are seeing. Cast shadows can add drama and mystery to a scene, particularly when the object or character casting the shadow is off camera.

Different light directions and angles offer a variety of mood options, and I’ve listed a few here:

  1. Direct Overhead Lights:
    • Tend to read as unnatural.
    • Can help create tension and drama, and how much depends on the light’s exposure and temperature.
  2. Angled Light from the side:
    • Defines form.
    • Reads as active and energetic.
    • Adds dramatic tension.
  3. Frontal light (slightly to the side and above, not directly in front):
    • Comfortable way of positioning light.
    • Keeps an object/character from being in too much shadow.
    • Good at defining form.
    • Reads as soft and friendly.
  4. Under Lighting:
    • Is the most unnatural of all the lighting directions.
    • Feels dramatic in spooky, creepy, threatening, and unnatural ways.

How you choose to render your light will always depend on the position and point of view of the audience, and the message that needs to be conveyed.

The Fundamentals of Light—Breaking Down The Parts

Even though we learn in steps and stages, I find it helpful to get the “lay of the land” because it provides a road map, and it’s nice to at least have some idea of what we’re doing, right? With that in mind, I have listed the major headings that are part of studying The Fundamentals of Light and broken out some detail for the area we’ve covered today.

Deep breath…

  1. Properties of Light
    • Light Sources
    • Types of Light
    • Terminology & Sphere Tests
    • Fall Off & Form Changes
    • Exposure
  2. Light & Surface Color
  3. Reflections
  4. Translucence & Transparency (Transmission)
  5. Light & Materials
  6. Atmospheric Effects & Atmospheric Perspective
  7. The Human Experience of Light
  8. Rendering/Visual Styles

Next Time: The Fundamentals of Light, Part 2!

Take a moment to think of your absolute favorite treat for relaxing and pampering yourself. See it, visualize it in your mind’s eye. Now…get yourself that treat! You have just made it through a massive amount of information in a relatively short(ish) amount of time.

Congratulations!

Thank you for hanging in there with me. I’ve tried to keep things clear and concise, but I know this was a lot to take in. I commend you, I thank you, and I am sending you virtual high fives and fist bumps!

We need some forms before we render light, so if you need guidance in that area I have some posts covering Form and The Fundamentals of Art to help.

The next couple of posts in my Fundamentals of Light series will cover exposure and fall off, and then absorption, reflection, and refraction of light wavelengths.

If I’ve confused you, if you have questions, or if I’ve gotten anything wrong, please message me in the comments and I’ll do my best to clear things up.

I hope you’ll join me for those as well.

Take care, and happy drawing everyone!


[i] https://en.wikipedia.org/wiki/Umbra,_penumbra_and_antumbra